Phase 8: add the Reference App wiki walkthrough (06_reference_app)

- four pages walking the vet sample: overview, domain & API, pipelines &
  worker, spec-driven client admin
- mkdocs nav section, index + start-an-app cross links
- bundle now exposes the walkthrough as wiki_reference_app_* modules

standards/src/wiki/06_reference_app/04_client_admin.md

@@ -0,0 +1,60 @@
+# Client Admin — the spec-driven frontend
+
+The client sample (`standards/src/templates/client/`) renders a full admin —
+auth pages, resource lists, forms, detail views — **from the server's
+`openapi.yaml`**, driven entirely by the x- extension fields. There are no
+hand-written screens per resource.
+
+## What ships
+
+A Vite + React + MUI app wiring the two Aetos packages:
+
+- **`@aetoskia/react-openapi`** — fetches `${VITE_API_BASE_URL}/openapi.json`,
+  builds the router and the resource admin from the spec's schemas and x-
+  fields (list columns, autocomplete, fk pickers, enum selects, hidden fields…)
+- **`@aetoskia/react-auth`** — login/register/logout against the auth-server
+  paths declared in the spec's `securitySchemes.bearerAuth`, and attaches the
+  JWT to every API call
+- a shared MUI theme (`src/shared-theme/`) and the shell
+  (`Header` / `Footer` / `Home`)
+
+`src/openapi-config.ts` is the only configuration:
+
+```ts
+export const specConfiguration: SpecConfiguration = {
+  specUrl: `${apiBase}/openapi.json`,
+  baseApiUrl: apiBase,
+  title: "Vet Admin",
+  getToken: () => tokenStore.get(),
+};
+```
+
+## Pair it with the sample server
+
+```bash
+cd apps/vet-sample-client
+printf 'VITE_API_BASE_URL=http://localhost:8020\nVITE_AUTH_BASE_URL=http://localhost:8020\n' > .env.local
+npm install
+npm run dev
+```
+
+Open the dev-server URL; the admin lists Parents, Pets, Treatments, Vets,
+Appointments and Jobs straight from the vet spec. Edit `openapi.yaml` on the
+server and the client follows on reload — the spec is the contract on both
+sides.
+
+## Where the x- extensions come from
+
+The canonical catalog lives in the react-openapi package
+(`spec-extensions.ts`, served to agents as the `specExtensions` module of the
+react-openapi MCP bundle). The worked examples on the server side are the
+`Job` schema (enum selects via `x-edit-as: select` + `x-ui-type: enum`,
+`x-hidden` field masks, `x-list-columns`) and the FK fields on `Appointment`
+(`x-fk: {resource: pets, prefetch: true}`).
+
+## CI
+
+The client ships a `drone-npm` shape (Type B in
+[Drone Pipelines](../lib/90_drone_pipelines/)) and follows the
+[Versioning](../lib/91_versioning/) standard (`package.json` +
+`CHANGELOG.md`).